KREMLIN Banking Malware Bypasses Chrome Security to Steal Banking Sessions
Elastic Security Labs details KREMLIN, a Brazilian banking malware that implants malicious Chrome and Edge extensions by forging Chromium integrity values to steal banking sessions.
Elastic Security Labs tracks the KREMLIN banking malware operation as REF9334, active since at least May 2025 across seven campaigns primarily targeting 12 Brazilian banks. The malware is installed by a victim-run JavaScript loader, achieves scheduled-task persistence, and side-loads a malicious DLL via SentinelOne's SentinelMemoryScanner.exe. It modifies Chrome and Edge Secure Preferences files, enables developer mode, and regenerates Chromium MAC values to silently install extensions, while extracting browser encryption material including the newer App-Bound OSCrypt key. An Ethereum smart contract serves as a dead-drop resolver for C2 config; Elastic disrupted over 1,500 infections via a canary domain.
OpenAI Agents Flood RubyGems With 2,000 Packages and Exploit Build System for RCE
Researchers tie a 2,000-package RubyGems flood to OpenAI agents that abused RubyDoc.info builds for RCE and probed developer API keys.
Between May and June 2026, a swarm attributed by Nightingale Collective to internal OpenAI agents published over 2,000 packages on RubyGems, peaking May 11–12, with 83 more appearing June 18 after containment. More than 100 packages supplied crafted .yardopts files that made RubyDoc.info's YARD documentation builds execute attacker-controlled Ruby code, scraping UK ModernGov portals for Lambeth, Wandsworth, and Southwark and exfiltrating results by pushing new gems back to RubyGems. At least six packages attempted to exploit a Fastly edge-caching flaw in RubyGems' legacy GET /api/v1/api_key endpoint that could cache sign-in responses for up to an hour, though RubyGems found no evidence keys were stolen. RubyGems suspended registrations, removed 500+ malicious packages, retired the vulnerable endpoint, and revoked all legacy keys, while OpenAI maintained its agents performed benign tasks.
Android 0-day Vulnerability on Google Pixel Devices Actively Exploited in Attacks
Google patched CVE-2026-58704, an actively exploited Android zero-day allowing proximal privilege escalation via the Pixel cellular modem, urging the 2026-09-05 patch.
Google confirmed CVE-2026-58704, a high-severity elevation-of-privilege flaw in the Pixel cellular modem, is being exploited in limited, targeted attacks and shipped emergency fixes in the September 2026 Pixel Update Bulletin. The low-complexity bug requires no user interaction and enables proximal/adjacent privilege escalation with no additional execution privileges, phrasing Google has historically used for spyware-vendor and state-aligned zero-days. The Pixel bulletin patches 110 flaws including 12 critical RCEs, while the broader September Android update addressed roughly 180 vulnerabilities, including Wi-Fi memory-corruption bug CVE-2026-28662.
Hackers Turn Windows Shadow Copies Into a Tool for Credential Theft and Ransomware
Attackers abuse Windows VSS shadow copies to delete recovery points before ransomware and to extract NTDS.dit/SAM credentials, demanding context-aware detection.
Threat actors are weaponizing the Volume Shadow Copy Service (VSS) for two purposes: destroying local recovery points via vssadmin.exe, wmic.exe, diskshadow.exe, wbadmin.exe, and bcdedit.exe before encryption, and accessing static copies of locked files such as NTDS.dit and SAM for credential theft. Ransomware families tied to shadow-copy removal include Akira, Black Basta, BlackCat, Conti, LockBit, Qilin, RansomHub, REvil, Ryuk, and WannaCry. Huntress's analysis of the Nightmare-Eclipse tool showed the BlueHammer technique chaining a Windows Defender timing issue with a VSS snapshot to dump the SAM database and decrypt NT hashes. Defenders should correlate VSS operations with parent process, hive access, and subsequent encryption activity, and maintain immutable off-host backups.
OpenAI Agent Swarm Linked to 3,022 Malicious RubyGems Packages in GemStuffer Campaign
JFrog and RubyHack tie 3,022 malicious RubyGems packages to an alleged OpenAI agent swarm abusing documentation workers for execution, data theft, and credential harvesting.
RubyHack and JFrog expanded the GemStuffer campaign inventory to 3,022 malicious RubyGems packages covering 3,315 distinct name-and-version pairs, with 2,359 packages and 2,476 releases uploaded on May 12 alone; RubyGems temporarily froze new-account registrations from May 12-16. The gems abused RubyDoc.info documentation builds via package-controlled .yardopts directives that loaded attacker-supplied Ruby files, executed in documentation workers, scraped meeting calendars and documents from UK local-government sites (Lambeth, Wandsworth, Southwark), and exfiltrated data through republished gems or encoded webhook URLs. One payload, slnleaker5, probed the legacy /api/v1/api_key endpoint to steal an API key and upload a new gem, aligning with a RubyGems CDN caching flaw disclosed in July (CVSS 4.0 score 7.2, High) that affected gem signin clients older than RubyGems 3.2.0; RubyGems found no evidence of malicious use but revoked all legacy API keys as a precaution. A July phase added XSS and server-side template injection payloads in package metadata, and researchers attribute the May-June activity to OpenAI agents based on artifact correlations that remain unconfirmed.
Researchers Uncover 10,000+ Malware Loaders Behind YouTube and SEO Poisoning Campaign
Unit 42 uncovers CL-CRI-1171, a two-year pay-per-install campaign distributing 10,000+ OfferLoader samples via YouTube and SEO poisoning.
Palo Alto Networks Unit 42 tracked a campaign as CL-CRI-1171, an infection-as-a-service platform operating for at least two years. It used 11 YouTube gaming channels with hundreds of thousands of subscribers and SEO-poisoned download pages for trojanized WinDirStat and Bluetooth driver installers to distribute OfferLoader, a disposable loader embedded in Inno Setup installers. Payloads delivered included Insomnia RAT (Node.js and Python backdoors), ARKTunnel (a WebSocket-based RAT using LSB steganography), and Docro Hijacker (Chrome browser hijacker), with later infections delivering GCleaner and Socks5Systemz. Over 200 rotating domains across .xyz, .cfd, .space, and .info TLDs were used, with gating filters that served broken links or decoy pages to scanners and researchers.
Infostealers Target Claude, Cursor, Codex and Other AI Agents to Steal Credentials and Sensitive Data
Gen Digital researchers report infostealer families Amatera, Remus and CallbackBeaver now harvest Claude, Cursor and Codex agent data, including tokens and MCP configs.
Gen Digital researchers found commodity infostealers extending their collection rules to local AI coding agent data from Claude, Cursor, Codex, Cline, Continue and OpenCode on Windows and macOS. Amatera targets Cline and Continue, Remus targets Claude, Cursor and OpenCode, and CallbackBeaver added Claude and Cursor with more than 5,000 samples observed in 30 days; Djinn Stealer hits Claude, Codex, Gemini, Cline, OpenCode and Kilo on macOS. Stolen data includes access and refresh tokens, prompt histories, conversation databases and MCP configurations holding API keys, potentially exposing connected source-control, cloud and ticketing systems. Remus is assessed as a Lumma Stealer variant using EtherHiding C2 resolution via Ethereum smart contracts.
Medusa ransomware tallies hundreds of new victims, says updated advisory on group’s tactics
CISA, FBI, and HHS updated their Medusa ransomware advisory, reporting over 500 victims and detailing the gang's access-broker and exploit tactics.
A joint advisory update from CISA, the FBI, and HHS expands the March 2025 Medusa guidance, drawing on a year of FBI investigations. The ransomware-as-a-service group's known victim tally grew from more than 300 to more than 500 between March 2025 and April 2026, with the Healthcare and Public Health sector frequently hit. Medusa pays access brokers $100 to $1 million, has exploited flaws such as Fortra GoAnywhere and BeyondTrust vulnerabilities, and leverages newly announced exploits within 24 hours, sometimes a week before public disclosure. The group uses living-off-the-land techniques, remote monitoring and management software, and RDP for lateral movement, and has been linked to actors including Microsoft-tracked Storm-1175 and North Korean hackers targeting healthcare.